It’s a case of damned if you do, damned if you don’t for the Laos government. The construction of a controversial mega-dam in Laos on the Mekong river poses threats to millions of people reliant on the Mekong as well as hundreds of freshwater species, but offers a hope of development for one of the poorest countries in the region.

The Mekong river. Photo: WWF/Adam Cathro

Earlier this month, the government of Laos announced that they would begin construction of the Xayaburi mega-dam project on the Mekong river. The hydroelectric dam would be the first major dam on the lower Mekong. The project is expected to bring in billions of dollars of much needed revenue for the Laos government. However, environmentalists and neighbouring countries have raised concerns about the dam’s effect on the Mekong ecosystem and the millions of people who depend on it for their livelihoods.

Construction underway at the Xayaburi dam site. Photo: International Rivers

Last week we highlighted a report from the IUCN addressing the state of freshwater biodiversity in the Indo-Burma region in South-East Asia. One of the biggest threats to freshwater biodiversity in the region is the ongoing construction of dams, particularly along the Mekong river.

The Mekong river runs through 6 different countries, starting in China and meandering its way down through Burma (Myanmar), Laos, Cambodia, Thailand and Vietnam before emptying in the South China Sea. It is the lifeblood for over 60 million people living on or near the expansive river and it also home to the highest concentration of fish species by area on the planet. There are over 1,000 known species throughout the Mekong, and scientists are worried that the dam could lead to the extinction of hundreds of freshwater species including one of the largest and most critically endangered freshwater fish in the world, the slightly strange-looking Mekong giant catfish.

Mekong giant catfish. Some specimens have been found weighing over 300kg and are more than 3m in length. Photo: National Geographic/Zeb Hogan

The proposed dam is a major threat to these people and the ecosystems of the Mekong due to its downstream effects. The effects of the dam are more than just impeding the flow of water though. It will also block the migration paths of numerous large fish species, capture nutrient sediments causing a decrease in water quality downstream, and change water temperatures. The overall effect would be to drastically alter the ecosystems in which more ‘generalist’ species would be favoured and the more environmentally sensitive endemic species would decline. This means that we could likely see a significant decrease in freshwater biodiversity as a result of this dam.

The construction for the dam has also been a point of international tension with other countries through which the Mekong flows. Cambodia and Vietnam have both raised concerns about the dams potential negative effects on fisheries and rice crops affecting the food security of their citizens dependent on the river. Thailand, who has agreed to buy 90% of the electricity generated from the dam, has expressed its support for the project, although local protects have occurred. The Unites States released a statement saying “the extent and severity of impacts from the Xayaburi dam on an ecosystem that provides food security and livelihoods for millions are still unknown.”

One of the many floating markets found along the length of the Mekong river.

Under the Mekong River Commission, an intergovernmental body established to promote the coordinated governance of the shared river, countries are supposed to consult with each other and reach a consensus before initiating any major projects. Although Cambodia and Vietnam have raised objections, Laos has stated that all concerns have been addressed and that it will be going ahead with the dam.

Laos, one of the poorest country in South-East Asia, has the right to development and a duty to lift its people out of poverty. But it should endeavour to do so in an appropriate and responsible way. The construction of dams on the Mekong and across the wider Indo-Burma region is perhaps inevitable as the countries of the area look to develop and meet the growing power needs of their citizens in a carbon constrained world.

What needs to happen then is that a greater consideration must be given to the human and environmental impacts of a project before and during its construction and, where possible, the utmost effect be taken to avoid or mitigate any negative effects. This is an important point as a further 10 mega-dams are proposed for the Mekong river (8 of them are in Laos) and the decision by Laos to push ahead with the Xayaburi dam despite concerns may set a worrying precedent.

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